1. R

    Vacuum in gas tank.

    After checking and double checking float bowl adjustment my bowl seemed to run out quickly and the motor would die. I looked at the fuel supply line and repaced the filter with a faster flowing filter. From the tiny metal bead type to a larger paper filter. Same probem, bowl ran dry. Is there...
  2. F

    Magneto contacts broken off. how to reattach?

    Hello everyone, sorry if I sound like a noob, but I never did this before and english isn't my first language. Anyway, I built my first motorized bicycle from a 26" mountain bike. (It's the "standard" engine 2 stroke engine nearly everyone uses.) The bike didn't start and I noticed the little...
  3. J

    Rusty crankshaft

    I recently disassembled my engine, to check everything and I was very disappointed. I used my bike every day, stored in a garage, so that's not the problem. The bearings are dry and the crankshaft started to rust. I'm using 1:30 mixture, Repsol Competition synthetic oil, the cylinder seems well...
  4. Ollie White

    Engine not starting, despite fuel and spark

    My 80cc engine from China (eBay) has not started since it was assembled a week or two ago. Fuel is getting to the engine, as the spark plug was wet when checked after cranking - for some reason it refuses to burst to life upon releasing the clutch. The engine will turn over after releasing the...
  5. Eddie Medley

    Engine speed

    I have 80cc engine that tops 18 mph at best with 38 tooth sprocket, speed carb. My old 80cc engine top 27 with 44 tooth sprocket with stock carb I had 49cc with 38 tooth sprocket speed can that went 19 mph 20 at best The engine now is sputtering a bit How can I fix this
  6. Losíf

    Centrifugal clutch problem, Help!

    So I just put together this 49cc 4stroke 7g t-belt engine onto my bike. It runs and all but a major issue is present guessing it's the centrificul clutch staying engaged. I can pedal the bike to start the engine like a 2stroke bike while not holding the manual clutch in. If I start the engine...
  7. H

    Clutch Clutch won't re-engage/disengage after starting engine

    Hey, sorry I'm not sure weather pulling the clutch in is dis engaging or engaging, but I have a problem with my little two stroke engine on my bike, the clutch will start the motor and disengage it when you (with lots of pressure on the brakes) stop. But as you are riding and try to pull in the...
  8. O

    high rev/ air leak

    so ive had my motorized bike for about 5 months, and it used to run perfectly, but recently i replaced the brake lever from a standard, to a double lever on the same handle. i dont know how this would change anything, but after that it runs really weak and take a long time to rev down. i cant...